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AorticDissection.com- Stanford University Responds to my
questions: |
Here's a the first organization that I got to respond to my
questionnaire found here: Stanford is a TREMENDOUS asset to this site
and all that they do!
http://www.aorticdissection.com/ER%20Doctor%20Questions.htm
The Responses:
Here's some questions that I want answered:
1. What if a man/woman 45 years of age came into your ER
department complaining of chest pains. What would be the first things
you would do to begin to rule out the possibility of an
AorticDissection?
Obviously ER physicians or primary care
providers have to be knowledgeable about a multitude of disease
processes. Whenever someone presents with chest pain, you have to
rule out the bad things first. This is based on statistical bell
curves and probability of a certain disease process. A 45 year old
male will be at greater risk of an MI (myocardial infarction/heart
attack) than a 45 year old female. With that being said, a 45 year
old, obese, diabetic, female with hypertension and a significant
smoking habit will be at a greater risk for an MI than a 45 year old
otherwise healthy male. With all that being said, the first thing I
would do to rule out a dissection would be to weigh the odds that
someone is at risk for a dissection or MI. From that point, the
history and physical exam will be the first and most important tool
for the primary care provider. If you listen to your patient and/or
the historian, they will tell you what is wrong with them. The clues
are in the history. The confirmation is in the physical examination.
The problem is that a lot of care providers do not have the time for
an “adequate” H/P and they jump to different diagnostic algorithms
without listening to the situation or patient. The fundamental reason
for this and possible solutions are way beyond the scope of
what you are looking for though.
In medicine as well as logic there is a
rule called Occam’s Razor. This essentially means that the most
simple answer or most obvious answer that fits the most variables
is the answer, no matter how improbable. If it walks like a duck
and talks like a duck, it’s probably a duck. If you hear hoof beats,
it’s probably a horse and not a zebra…unless you are in an area
heavily populated by zebras. As a care provider you have to get an
idea if the patient is at risk for an MI or dissection. From there,
the history will either confirm or contradict the first impression.
If it contradicts your initial assessment, you must investigate
further and broaden your “what ifs”. After that, the treatment
protocols are in place for medications (if their BP is high then
control it with beta blockers if they are patient category X or with
ACEIs if they are patient category Y [meaning with concomitant disease
processes], treat pain with morphine, etc…) as well as procedures to
be ordered such as labs (CBC, Chem panels, troponins, Cks [both are
markers of tissue damage that are noticeable at different times], and
diagnostic studies such as an EKG, echocardiogram, chest Xray, CT, or
a CTA.
2. Is there a check list that you would use to differentiate
from these?
Yes and No. The presentation in
combination with the history and physical exam will provide you with a
mental checklist but this is formulated by each practitioner based
upon their knowledge and experiences.
3. How would you be able to rule out that it was not a heart
attack?
If the patient is a 45 year old male with
a history of high lipids, exertional chest pain, high blood pressure,
tachycardia, high or low blood pressure, diaphoretic, with pain
raditating in specific patterns, with classic or suspicious EKG
findings, and his cardiac markers are abnormal, then I would think
that it was probably a heart attack . If the patient is a 45 year old
otherwise healthy male with a remote history of a murmur, chest and
back pain of a tearing quality, with absent femoral pulses and a
family history of early unexplained deaths, then I would think that it
was more than likely an aortic dissection, with the caveat that type A
dissections can shear off or cause obstruction of a coronary artery
causing myocardial damage. This is essentially a heart attack
caused by a type A aortic dissection and is probably part of the
reason why a type A aortic dissection is so lethal.
4. How would you rule out that it was not a pulmonary embolism?
This would go back to the presentation and history
and physical examination. PE patients have a plethora of
presentations and symptomatology so they are particularly perplexing
and PE should be considered in any patient presenting with CP or
dyspnea. Any of the above presentations in conjunction with sudden
chest wall pain without a good history of trauma or strain to the area
is particularly worrisome for a PE. The only real way to rule out a
PE in most cases is to get a multidector computed tomographic
angiogram (MDCTA or CTA) to look at the pulmonary vessels. This is
the current diagnostic test of choice and the criterion for ruling in
or ruling out a PE. Other studies such as V/Q lung scans can also
help rule in or rule out a PE if high resolution CTAs are unavailable.
5. Would there be clues like, different BP readings that you
detect that might start you thinking down the possible AD path?
Intense Back pain between shoulders? Numbness in limbs?
Yes. In addition to the clues gathered in the
history and other clues in the subjective data (labs etc…), any
discrepancy between upper and lower extremity pulses or any
discrepancy between one side or the other side’s pulses would be a red
flag. This includes any numbness or paresthesias in any different
pattern of upper verses lower or right verses left. These types of
symptoms would be more specific to an AD than intense back or
intra-scapular pain (as that could represent far more diagnostic
possibilities). Any of these symptoms in addition to the previously
mentioned presentation +/- the patient history would be a clue to an
aortic dissection.
6. Would you act differently if the patient or loved one with
them said you had a history of ADs in the family? Would you go to the
CT scan immediately versus still trying to determine if it was a Heart
Attack?
Yes and Yes as aortic dissections, especially in a
younger person can be linked genetically or in familial clusters. If
the patient is older and the possibility of atherosclerotic causes of
an aortic aneurysm +/- dissection increase, then it would not be as
significant. However, a TTE (transthoracic echocardiogram) in the
hands of an experienced sonographer can be an invaluable tool as
well. There are many different ways to view the aortic dissection
flap via TTE and this can serve as a quick, easy, and financially
soluble solution in an emergency situation. Of course, not all
dissection flaps are visible on TTE because of their location,
morphology, or because of the patients anatomy; however, it can be a
useful tool that should be included in your workup.
7. Would there be a particular blood test such as a D-Dimer that
you would run? What if it did come back high for a Pulmonary Embolism?
Would you order a CT right away?
Yes. The laboratory reports can be especially
important. If the D-dimer is high or marginal, then the current
algorithm says yes-get a CTA. If it is low, then a CTA is not
warranted. If Ck, CkMB, and/or troponins are abnormal in the presence
of the CP presentation, then yes-an MI is likely. If the creatinine
or liver functions are abnormal in the previous presentation, then I
would think that a dissection is likely (the dissection flap can
occlude or shear off different vessels and cause different
constellations of organ malfunction/damage) and would head for the CTA.
8. Do you feel that you have had adequate training on the
subject of Aortic Dissections to be able to properly detect it if it
was your loved one you were working on?
Yes.
9. What gives you the "green" light to order a CT scan as you
since your patient might be suffering from an ascending aortic
dissection?
Any of the above mentioned scenarios in addition to
the number one tool in a clinician’s tool box, clinical judgment!
Intuition, experience, knowledge, and praxis all lead to more accurate
clinical judgment. If a care provider has treated a patient for an MI
and it ended up being an aortic dissection, they almost always will
include that work-up and possibility in the next CP presentation.
Care providers are human and act based on our knowledge influenced by
our experience. See the aforementioned analogy-if I lived in Montana
and heard hoof beats, I would think it was a horse. But if I moved to
Zimbabwe or was on a mission trip, I would amend that based on the
knowledge and experience of seeing zebras or any other hoofed animal
in that location. All of this is part of clinical judgment: knowledge
in the presence of experience and praxis (action based on critical
thinking and analysis of a situation).
10. How often do you get refresher course on the subject? Who
provides them? How many AD's have you detected before? Did you use
that check list as mentioned before? Have you changed your procedures
on the ability to detect these based on what you have learned in the
past?
I am by training a Family Nurse Practitioner and
nationally certified by the American Association of Nurse
Practitioners. I am currently the Nurse Practitioner for the Thoracic
Aortic Surgery Unit at Stanford Hospital and Clinics, where I work for
Doctors Craig Miller and Scott Mitchell. I am responsible for working
up our elective cases in the outpatient setting, meaning I review CTAs,
echos, caths, and records and put into place the patient care plan. I
do not see emergency cases in the ER at Stanford. However, I also
work per diem as an NP in several urgent care centers around the bay
area and we often get patients with chest pain. I attend multiple
conferences, symposia, or lectures annually to continually educate
myself. These are normally offered through professional organizations
such as the STS, AATS, or AANP and often co-sponsored by finances from
industry leaders.
Michael Sheehan
Nurse Practitioner for
Thoracic Aortic Surgery
Stanford
University Medical Center
300 Pasteur Drive
2nd Floor,
Falk Building
Stanford,
CA 94305-5407
PH: 650-725-0524
FX: 650-725-3846
"to cure-rarely, to treat-often, to care-always"
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